ppp: options header sanity check

4 files changed, 51 insertions, 19 deletions

diff --git a/accel-pppd/ppp/ppp_ccp.c b/accel-pppd/ppp/ppp_ccp.c
index 88adc30b..6b97215c 100644
--- a/accel-pppd/ppp/ppp_ccp.c
+++ b/accel-pppd/ppp/ppp_ccp.c
@@ -387,14 +387,12 @@ static int ccp_recv_conf_req(struct ppp_ccp_t *ccp, uint8_t *data, int size)
 	while (size > 0) {
 		hdr = (struct ccp_opt_hdr_t *)data;
 
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		ropt = _malloc(sizeof(*ropt));
 		memset(ropt, 0, sizeof(*ropt));
 
-		if (hdr->len > size)
-			ropt->len = size;
-		else
-			ropt->len = hdr->len;
-			
 		ropt->hdr = hdr;
 		ropt->state = CCP_OPT_NONE;
 		list_add_tail(&ropt->entry, &ccp->ropt_list);
@@ -483,6 +481,9 @@ static int ccp_recv_conf_rej(struct ppp_ccp_t *ccp, uint8_t *data, int size)
 	while (size > 0) {
 		hdr = (struct ccp_opt_hdr_t *)data;
 		
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		list_for_each_entry(lopt, &ccp->options, entry) {
 			if (lopt->id == hdr->id) {
 				if (!lopt->h->recv_conf_rej)
@@ -521,6 +522,9 @@ static int ccp_recv_conf_nak(struct ppp_ccp_t *ccp, uint8_t *data, int size)
 	while (size > 0) {
 		hdr = (struct ccp_opt_hdr_t *)data;
 		
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		list_for_each_entry(lopt, &ccp->options, entry) {
 			if (lopt->id == hdr->id) {
 				if (conf_ppp_verbose) {
@@ -561,6 +565,9 @@ static int ccp_recv_conf_ack(struct ppp_ccp_t *ccp, uint8_t *data, int size)
 	while (size > 0) {
 		hdr = (struct ccp_opt_hdr_t *)data;
 		
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		list_for_each_entry(lopt, &ccp->options, entry) {
 			if (lopt->id == hdr->id) {
 				if (conf_ppp_verbose) {
diff --git a/accel-pppd/ppp/ppp_ipcp.c b/accel-pppd/ppp/ppp_ipcp.c
index aee0317d..63818e8c 100644
--- a/accel-pppd/ppp/ppp_ipcp.c
+++ b/accel-pppd/ppp/ppp_ipcp.c
@@ -392,13 +392,14 @@ static int ipcp_recv_conf_req(struct ppp_ipcp_t *ipcp, uint8_t *data, int size)
 	while (size > 0) {
 		hdr = (struct ipcp_opt_hdr_t *)data;
 
+		if (!hdr->len || hdr->len > size)
+			break;
+		
 		ropt = _malloc(sizeof(*ropt));
 		memset(ropt, 0, sizeof(*ropt));
 
-		if (hdr->len > size)
-			ropt->len = size;
-		else
-			ropt->len = hdr->len;
+		ropt->len = hdr->len;
+
 		ropt->hdr = hdr;
 		ropt->state = IPCP_OPT_NONE;
 		list_add_tail(&ropt->entry, &ipcp->ropt_list);
@@ -503,7 +504,10 @@ static int ipcp_recv_conf_rej(struct ppp_ipcp_t *ipcp, uint8_t *data, int size)
 
 	while (size > 0) {
 		hdr = (struct ipcp_opt_hdr_t *)data;
-		
+	
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		list_for_each_entry(lopt, &ipcp->options, entry) {
 			if (lopt->id == hdr->id) {
 				if (!lopt->h->recv_conf_rej)
@@ -542,6 +546,9 @@ static int ipcp_recv_conf_nak(struct ppp_ipcp_t *ipcp, uint8_t *data, int size)
 	while (size > 0) {
 		hdr = (struct ipcp_opt_hdr_t *)data;
 		
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		list_for_each_entry(lopt, &ipcp->options, entry) {
 			if (lopt->id == hdr->id) {
 				if (conf_ppp_verbose) {
@@ -582,6 +589,9 @@ static int ipcp_recv_conf_ack(struct ppp_ipcp_t *ipcp, uint8_t *data, int size)
 	while (size > 0) {
 		hdr = (struct ipcp_opt_hdr_t *)data;
 		
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		list_for_each_entry(lopt, &ipcp->options, entry) {
 			if (lopt->id == hdr->id) {
 				if (conf_ppp_verbose) {
diff --git a/accel-pppd/ppp/ppp_ipv6cp.c b/accel-pppd/ppp/ppp_ipv6cp.c
index a984e43a..5479f316 100644
--- a/accel-pppd/ppp/ppp_ipv6cp.c
+++ b/accel-pppd/ppp/ppp_ipv6cp.c
@@ -392,13 +392,12 @@ static int ipv6cp_recv_conf_req(struct ppp_ipv6cp_t *ipv6cp, uint8_t *data, int
 	while (size > 0) {
 		hdr = (struct ipv6cp_opt_hdr_t *)data;
 
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		ropt = _malloc(sizeof(*ropt));
 		memset(ropt, 0, sizeof(*ropt));
 
-		if (hdr->len > size)
-			ropt->len = size;
-		else
-			ropt->len = hdr->len;
 		ropt->hdr = hdr;
 		ropt->state = IPV6CP_OPT_NONE;
 		list_add_tail(&ropt->entry, &ipv6cp->ropt_list);
@@ -504,6 +503,9 @@ static int ipv6cp_recv_conf_rej(struct ppp_ipv6cp_t *ipv6cp, uint8_t *data, int
 	while (size > 0) {
 		hdr = (struct ipv6cp_opt_hdr_t *)data;
 		
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		list_for_each_entry(lopt, &ipv6cp->options, entry) {
 			if (lopt->id == hdr->id) {
 				if (!lopt->h->recv_conf_rej)
@@ -542,6 +544,9 @@ static int ipv6cp_recv_conf_nak(struct ppp_ipv6cp_t *ipv6cp, uint8_t *data, int
 	while (size > 0) {
 		hdr = (struct ipv6cp_opt_hdr_t *)data;
 		
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		list_for_each_entry(lopt, &ipv6cp->options, entry) {
 			if (lopt->id == hdr->id) {
 				if (conf_ppp_verbose) {
@@ -582,6 +587,9 @@ static int ipv6cp_recv_conf_ack(struct ppp_ipv6cp_t *ipv6cp, uint8_t *data, int
 	while (size > 0) {
 		hdr = (struct ipv6cp_opt_hdr_t *)data;
 		
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		list_for_each_entry(lopt, &ipv6cp->options, entry) {
 			if (lopt->id == hdr->id) {
 				if (conf_ppp_verbose) {
diff --git a/accel-pppd/ppp/ppp_lcp.c b/accel-pppd/ppp/ppp_lcp.c
index fa23436d..955b859d 100644
--- a/accel-pppd/ppp/ppp_lcp.c
+++ b/accel-pppd/ppp/ppp_lcp.c
@@ -368,14 +368,12 @@ static int lcp_recv_conf_req(struct ppp_lcp_t *lcp, uint8_t *data, int size)
 	while (size > 0) {
 		hdr = (struct lcp_opt_hdr_t *)data;
 
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		ropt = _malloc(sizeof(*ropt));
 		memset(ropt, 0, sizeof(*ropt));
 
-		if (hdr->len > size)
-			ropt->len = size;
-		else
-			ropt->len = hdr->len;
-
 		ropt->hdr = hdr;
 		ropt->state = LCP_OPT_NONE;
 		list_add_tail(&ropt->entry, &lcp->ropt_list);
@@ -461,6 +459,9 @@ static int lcp_recv_conf_rej(struct ppp_lcp_t *lcp, uint8_t *data, int size)
 	while (size > 0) {
 		hdr = (struct lcp_opt_hdr_t *)data;
 		
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		list_for_each_entry(lopt, &lcp->options, entry) {
 			if (lopt->id == hdr->id) {
 				if (conf_ppp_verbose) {
@@ -503,6 +504,9 @@ static int lcp_recv_conf_nak(struct ppp_lcp_t *lcp, uint8_t *data, int size)
 	while (size > 0) {
 		hdr = (struct lcp_opt_hdr_t *)data;
 		
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		list_for_each_entry(lopt,&lcp->options,entry) {
 			if (lopt->id == hdr->id) {
 				if (conf_ppp_verbose) {
@@ -543,6 +547,9 @@ static int lcp_recv_conf_ack(struct ppp_lcp_t *lcp, uint8_t *data, int size)
 	while (size > 0) {
 		hdr = (struct lcp_opt_hdr_t *)data;
 		
+		if (!hdr->len || hdr->len > size)
+			break;
+
 		list_for_each_entry(lopt, &lcp->options, entry) {
 			if (lopt->id == hdr->id) {
 				if (conf_ppp_verbose) {